The present investigation was carried out at Fertilizer Research Station Uttari Pura, C.S. Azad University of Agric. & Technology, Kanpur, in Inceptisol, to investigate the effect of various doses of K (K0, K40, K80, K120 kg ha-1) and Zn (Zn0, Zn2.5, Zn5, Zn10 kg ha-1) under direct application in rice and their residual effect in wheat under rice-wheat cropping system. The experimental soil was deficient in N, P, and Zn and medium in K and S. The uniform doses of 150 kg N, 75 kg P2O5 and 60 kg S ha-1 were applied in rice crop. The wheat crop was fertilized with 120 kg N, 60 kg P2O5, and 40 kg S ha-1. The wheat crop was allowed to subsist on residual amount of K and Zn. The results indicated that yield of grain and straw were significantly increased with the application of K and Zn in rice and their residual effect in wheat crop. Grain yield of rice and wheat were increased by 55.27 percent and 29.00 percent and straw yield increased by 83.76 percent and 46.73 percent respectively with the application of K and Zn over their respective control. The maximum economic yield of grain 5025 and 4751 kg ha-1, the optimum doses of K and Zn in present study would be 105.57 kg K ha-1 and 6.95 kg Zn ha-1, respectively. A dose of K80Zn5 came out to be the best for most of the characters of both the crops under study.